As well known to those skilled in the art, since a mobile terminal is generally carried in a user's pocket or around a use's neck, it is desirable that a mobile terminal is light in weight and small in size.
In the meantime, the technology of obtaining a lightweight and small-sized battery for the mobile terminal has been pursued through the development of a nickel-cadmium (Ni—Cd) battery, a nickel-hydrogen (Ni—H) battery, a lithium-ion (Li-ion) battery, etc. However, since the battery technology lags behind the technology of developing a semiconductor that is mounted in the main body of the mobile terminal, there occurs a problem in which the battery of the mobile terminal is heavier and larger than the main body of the mobile terminal.
In order to improve the performance of the battery, the inventor of the present invention proposed the invention of Unexamined Korean Pat. Publication No. 98-87892 entitled Storage Battery with a Solar Cell for a Mobile terminal”. The patent discloses a battery that allow the battery to be charged by various light, thereby reducing inconvenience of charging the battery.
However, since the battery of the patent is formed by attaching one or two solar cells to one or two surfaces of the battery, the battery must be detached from the mobile terminal or the mobile terminal must be turned upside down to be charged by light, thereby increasing the inconvenience of charging the battery using light.
Additionally, Korean Pat. Publication No. 94-3280 entitled “Mobile terminal with a Solar Cell and Power Supply thereof” discloses a mobile terminal in which a solar cell is provided on the upper surface of the mobile terminal together with an data display that is always exposed to the outside, thereby allowing the battery to be charged by light in a normal state.
However, since the solar cell is disposed together with a receiver portion in the vicinity of the data display on the upper surface of the mobile terminal, there occurs a shortcoming in which the size of the solar cell is limited. As a result, the solar cell is not practicable to the mobile terminal that consumes a great deal of electric power because the mobile terminal must produce the high frequency output of 600 mW.